<template>
    <el-breadcrumb class="app-breadcrumb" separator="/">
        <transition-group name="breadcrumb">
            <el-breadcrumb-item v-for="(item, index) in breadcrumbs" :key="item.path">
                <span v-if="item.redirect === 'noredirect' || index === breadcrumbs.length-1" class="no-redirect">{{ $t("route." + item.meta.title) }}</span>
                <a v-else @click.prevent="handleLink(item)">
                    {{ $t("route." + item.meta.title) }}
                </a>
            </el-breadcrumb-item>
        </transition-group>
    </el-breadcrumb>
</template>

<script lang="ts">
import pathToRegexp from "path-to-regexp";
import { Component, Vue, Watch } from "vue-property-decorator";
import { RouteRecord, Route } from "vue-router";

@Component({
    name: "Breadcrumb"
})
export default class extends Vue {
    private breadcrumbs: RouteRecord[] = [];

    @Watch("$route")
    private onRouteChange(route) {
        // if you go to the redirect page, do not update the breadcrumbs
        if (route.path.startsWith("/redirect/")) {
            return;
        }
        this.getBreadcrumb();
    }

    created() {
        this.getBreadcrumb();
    }

    private getBreadcrumb() {
        let matched = this.$route.matched.filter(
            item => item.meta && item.meta.title
        );
        const first = matched[0];
        if (!this.isDashboard(first)) {
            matched = [
                {
                    path: "/dashboard",
                    meta: { title: "dashboard" }
                } as RouteRecord
            ].concat(matched);
        }
        this.breadcrumbs = matched.filter(item => {
            return (
                item.meta && item.meta.title && item.meta.breadcrumb !== false
            );
        });
    }

    private isDashboard(route: RouteRecord) {
        const name = route && route.name;
        if (!name) {
            return false;
        }
        return (
            name.trim().toLocaleLowerCase() === "Dashboard".toLocaleLowerCase()
        );
    }

    private pathCompile(path: string) {
        const { params } = this.$route;
        const toPath = pathToRegexp.compile(path);
        return toPath(params);
    }

    private handleLink(item: any) {
        const { redirect, path } = item;
        if (redirect) {
            this.$router.push(redirect);
            return;
        }
        this.$router.push(this.pathCompile(path));
    }
}
</script>

<style lang="less" scoped>
.app-breadcrumb {
    left: -100px;
    -webkit-transition: all 0.5s ease-in;
    -moz-transition: all 0.5s ease-in;
    transition: all 0.5s ease-in;
}
.el-breadcrumb__inner,
.el-breadcrumb__inner a {
    font-weight: 400 !important;
}

.app-breadcrumb.el-breadcrumb {
    display: inline-block;
    font-size: 14px;
    line-height: 50px;
    margin-left: 8px;

    .no-redirect {
        color: #97a8be;
        cursor: text;
    }
}
</style>
